There have been many and various attempts at creating an ignitor, more commonly described as a sparkplug, for combusting fuel in an internal combustion engine. Behind these ignitors, in the ignition circuit, have been many devices designed to increase the effectiveness of the ignitor. The attempts at creating a more efficient ignitor or increasing the effectiveness of the ignitor can be described as conventional sparkplugs with modifications to the electrodes and/or electrode spacing, capacitors/condensers in parallel with the ignition circuit, or devices interrupting the high voltage ignition pulse. While these attempts do effect, to some degree, the dynamics of the spark event, they are unnecessarily complex, costly, and inefficient.
U.S. Pat. No. 3,683,232, issued to Baur, discloses a sparkplug cap designed to increase the sparking power. The cap has internal capacitance of an unknown quantity. Without knowing the size of the capacitor, it is impossible to determine the increase of power, and it is very likely that a capacitor of high capacitance as claimed would, in fact, deplete the ignition voltage, precipitating a misfire and causing the engine to cease operation. It is very likely the Baur device requires an ignition system which is significantly higher in output energy than is commonly found on internal combustion engines.
U.S. Pat. No. 4,751,430, issued to Muller et al., discloses a sparkplug connector comprising a storage capacitor coaxial with an ignition transformer, which is fitted onto a sparkplug disposed deep in a spark plug hole. Such an arrangement, for the same reason as in Baur, can cause the engine to cease operation.
In U.S. Pat. No. 5,272,415, issued to Griswold et al., the method is different from Muller et al. and Baur, but the purpose of inserting a capacitor in parallel with the ignition circuit at the sparkplug raises the same concerns as Muller et al. and Baur, and causes a further problem of excess radio frequency interference (RFI). In vehicles manufactured in the 1990's, there is an increasing use of microprocessors to monitor and modify engine functions based on present conditions. These microprocessors are very sensitive to RFI emanations, and they will misfunction or fail as the frequency of a ringing capacitive discharge occurs in the same range as the operating frequency of the microprocessors.
U.S. Pat. No. 1,148,106, issued to Lux, discloses the addition of a condenser arranged in the positive electrode of a sparkplug in combination with multiple sparkplug gaps by which the resistance is diminished at the sparkplug gap, thereby obtaining improved operation of the sparkplug. The resistance of the sparkplug gap, whether single or multiple, is directly related to the pressure at the gap and the distance between the positive and negative electrodes of the sparkplug. In the case of multiple electrodes, it is dependent on the distance between the closest positive and negative electrode. A "silent" capacitive discharge between a pair of opposing electrodes effectively reduces the resistance between that pair of electrodes and the ignition spark is generated there rather than at a different pair where no ionization occurred. In Lux, the reduction of the resistance at a spark gap distant from the fuel mixture through a "silent" discharge forces the spark to occur at the "silent" pair of electrodes, which might or might not have fuel present to ignite. It is possible to ensure the proper operation of the spark while not igniting the fuel charge at all.